| Autor: |
Otto Zeman, Gregory A. Blaisdell |
| Rok vydání: |
1991 |
| Předmět: |
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| Zdroj: |
Advances in Turbulence 3 ISBN: 9783642844010 |
| Popis: |
This paper reports on recent advances in modeling and direct numerical simulations (DNS) of compressible turbulent flows. In the second-order equations, two principal compressibility terms have been identified: the dilatation dissipation (∈ d ) and the pressure-dilatation correlation (II d ). The dilatation dissipation arising from the occurence of shock-like events is treated by the theory of Zeman. A first order approximation to II d in homogeneous turbulence is shown to be \(I{I_d}\alpha - D\overline {{p^2}} /Dt.\) The rate of change of the pressure variance \(\overline {{p^2}}\) is proposed to be governed by nonlinear relaxation (on the acoustic time scale) to its equipartition value. The effect of dilatation dissipation is illustrated by comparing experiments and results of a second-order closure model (SOC) for compressible shear layers. DNS data in decaying, and shear-driven homogeneous turbulence are utilized to illustrate the initial-value dependence of turbulence evolution and to verify the proposed model for pressure-dilatation correlation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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